[Tyson]

This is a good response for ANY speaker, but for an OB speaker (which has inherent issues w/FR), I'm pretty ecstatic with this...

[jtwrace]

Tyson,

I'd recommend you go to File > Save bitmap Images > then click the one that you want.  It would be much easier to read and I've been keeping them in a folder as well. 

[jtwrace]

This is actually the speakers measured in the center of my room, tilted back, to give me the least # of reflections. 
 

The only problem is that's not what your listening to.  It makes for a better measurement but it's not really what you're listening to. 

Have you measured them together as you would listen to them?  If so, that's what you (and I) should look at. 

[saisunil]

Thanks for Sharing ...
Amazing Frequency Response 20 Hz and ~ -10db wow!

[Tyson]

The only problem is that's not what your listening to.  It makes for a better measurement but it's not really what you're listening to. 

Have you measured them together as you would listen to them?  If so, that's what you (and I) should look at. 

I have.  Very little effect on anything above 500hz (the beauty of coax design!!), but a lot of difference below that.  I have separate EQ settings saved, so I can dial in whichever is best for where I happen to be listening from that day - either the sweet spot, from a chair off to the side, or "up and about".  Gotta love the DCX

[jtwrace]

I have.  Very little effect on anything above 500hz (the beauty of coax design!!), but a lot of difference below that.  I have separate EQ settings saved, so I can dial in whichever is best for where I happen to be listening from that day - either the sweet spot, from a chair off to the side, or "up and about".  Gotta love the DCX

Can we see one of them?  Speakers in the listening position, mic at listening seat, both speakers on.  The < 500 Hz is what I'm really interested in.

[Tyson]

I overwrote them when I took the above measurements   But, I'll try to get something measured in the next day or two.  I'm a bit constrained because my wife isn't working at the moment and we had to take my daughter out of daycare on most days, so windows of opportunity to do measurements are few and far between these days....

[jtwrace]

I overwrote them when I took the above measurements   But, I'll try to get something measured in the next day or two.  I'm a bit constrained because my wife isn't working at the moment and we had to take my daughter out of daycare on most days, so windows of opportunity to do measurements are few and far between these days....

Gotcha!  Do you have a lot of room treatments?  Are you using a lot of eq?

[Tyson]

Room treatments?  Does thick carpet and heavy leather furniture count?  Hehe, nothing other than that, doesn't pass the WAF

Define "a lot of EQ"    Yes, I'm using a fair bit.  Two corrections in the bass, 2 in the mids, and 3 in the highs.  I should note that part of that is because I don't have the corrections that Danny built into the passive crossover, so I'm doing the corrections directly on the raw driver responses.  This is actually very common, it's similar to when I had my last set of active speakers (boxes), and used SEAS, Scan-Speak, Peerless, etc... All of them required about the same level of correction.

[Tyson]

Oh, and I should also note that I measure 30 degrees off axis.  I find it's a closer approximation of the sound I actually hear when listening.  When I do On Axis, there's less need for EQ, but it never really sounds right to me.

[jtwrace]

Room treatments?  Does thick carpet and heavy leather furniture count?  Hehe, nothing other than that, doesn't pass the WAF

Define "a lot of EQ"    Yes, I'm using a fair bit.  Two corrections in the bass, 2 in the mids, and 3 in the highs.  I should note that part of that is because I don't have the corrections that Danny built into the passive crossover, so I'm doing the corrections directly on the raw driver responses.  This is actually very common, it's similar to when I had my last set of active speakers (boxes), and used SEAS, Scan-Speak, Peerless, etc... All of them required about the same level of correction.

OK.  Speaking of raw response.  Post the raw not smoothed.   

[Tyson]

Sure thing.  The dip you see at 100hz fills in when the speaker is place back near the wall:

 

[Tyson]

The other thing I should note for other intrepid travelers on the fully active road - you must trust your EARS!

Measurements will get you most of the way there, but if you get everything measuring well (as I have here), and it's still not quite "right", you must be willing to experiment.  ESPECIALLY with something as powerful as a DCX, you have pretty much absolute control over what is coming out of your speakers (limited only by the quality of the drivers themselves). 

So, for me, the raw response posted above results in a bit of an opaque sound, with lower mids a bit emphasized and highs a bit recessed.  So, I bump the tweeter control up by 1 db.  Not enough.  2 db.  OK, that's closer.  But the mids still sound muddy, and the highs a bit disconnected.  Next, drop the 700hz cut by a db and drop the 350hz boost by a 1 db.

Ah, once you are in the ballpark, it's these little changes that make all the difference.  Much like swapping cables or tubes, these type of fine-tuning adjustments take the overall system from "pretty good" to "great".

[rajacat]

When you get it right have you considered taking the settings and building a regular passive crossover again? Does the DCX extract a price i.e. a slight negative impact on sound quality when compared to an optimized passive crossover.

It certainly seems that an active crossover is a tweakers dream. Let's say you change the position of a large object such as a couch, you can then go to the DCX and make an adjustment to put things back into balance.

Maybe those last little adjustments compensate for your individual hearing preferences brought about by the shape of your ears, compensation for hearing loss in certain frequencies, etc. Actually ears are like little horns that take in the sound and no two are alike. The last adjustments make the FR flat subjectively whereas
the DCX does it objectively.
-Roy

[brj]

Active crossovers are a disadvantage because they add more complexity (amps and cables) to a system than many people are willing to tolerate.  If you're willing to tolerate it, however, there are other advantages besides that of tweaking to your heart's content.  One of the big advantages of an active setup is that the amps are directly coupled to the drivers, and you avoid many impedance issues as a result.  You can "tune" the amp selection to each driver individually, both electrically (capacitance, inductance, damping factor, etc.) and sonically (tubes or class A on tweeters, SS or class D on woofers, etc.)

A potentially useful article on the topic: Active vs Passive Crossovers

Going back to a passive crossover gives up these advantages.

[Tyson]

brj, you are absolutely right, of course, and it's one of the main reasons I keep coming back to an active setup myself.  One caveat is noise - with a 106db sensitive tweeter that has no passive parts in front of it to pad it down, you WILL hear any noise your amp, preamp, or source is producing.  Just something to be aware of if going down this road.

[brj]

Good point on the sensitivity to system noise.  The more efficient the driver/speaker, the more sensitive you are.  (Horn speakers would have the same problem, for example.)

Do you not have a small cap on the tweeter just to protect it?  I know this is especially important with ribbon tweeters, but I would think that even a more traditional tweeter could get fried from any DC dumped into the line at system startup, etc..

[Tyson]

Nope, no cap.  I know it's a theoretical problem but I have transfomer coupled outputs on my tube amps, so I think they are reasonably protected. (crosses fingers).

[jtwrace]

Do you not have a small cap on the tweeter just to protect it?  I know this is especially important with ribbon tweeters, but I would think that even a more traditional tweeter could get fried from any DC dumped into the line at system startup, etc..

That's exactly what I did on my ribbon tweeter when I built a diy pair of speakers. 

[mgalusha]

Nope, no cap.  I know it's a theoretical problem but I have transfomer coupled outputs on my tube amps, so I think they are reasonably protected. (crosses fingers).

One good power bump from Excel Energy may convince you otherwise. Not DC but what would be a big thump in a woofer may take a CD with it. Pro compression drivers are better at tolerating this than a fragile ribbon or a standard 25mm tweeter but I wouldn't count on it surviving. Just my $0.02 worth.